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971.
We investigate the possibility of inducing the cosmological constant from extra dimensions by embedding our four-dimensional
Riemannian space-time into a five-dimensional Weyl integrable space. Following the approach of the space-time-matter theory
we show that when we go down from five to four dimensions, the Weyl field may contribute both to the induced energy-tensor
as well as to the cosmological constant Λ, or more generally, it may generate a time-dependent cosmological parameter Λ(t). As an application, we construct a simple cosmological model in which Λ(t) has some interesting properties. 相似文献
972.
Ramakrishna Bandi Alexandre Fotue Tabue Edgar Martínez-Moro 《Designs, Codes and Cryptography》2018,86(10):2247-2254
Let \(\texttt {R}\) be a finite commutative Frobenius ring and \(\texttt {S}\) a Galois extension of \(\texttt {R}\) of degree m. For positive integers k and \(k'\), we determine the number of free \(\texttt {S}\)-submodules \(\mathcal {B}\) of \(\texttt {S}^\ell \) with the property \(k=\texttt {rank}_\texttt {S}(\mathcal {B})\) and \(k'=\texttt {rank}_\texttt {R}(\mathcal {B}\cap \texttt {R}^\ell )\). This corrects the wrong result (Bill in Linear Algebr Appl 22:223–233, 1978, Theorem 6) which was given in the language of codes over finite fields. 相似文献
973.
Additive cyclic codes over Galois rings were investigated in Cao et al. (2015). In this paper, we investigate the same problem but over a more general ring family, finite commutative chain rings. When we focus on non-Galois finite commutative chain rings, we observe two different kinds of additivity. One of them is a natural generalization of the study in Cao et al. (2015), whereas the other one has some unusual properties especially while constructing dual codes. We interpret the reasons of such properties and illustrate our results giving concrete examples. 相似文献
974.
Edgar Lee Stout 《Proceedings of the American Mathematical Society》2006,134(8):2303-2308
Every continuous function on a compact, holomorphically convex, real-analytic subset of can be approximated uniformly by functions holomorphic on the set.
975.
Pinning and depinning of driven drops on heterogeneous substrates is studied as a function of the driving and heterogeneity amplitude. Two types of heterogeneity are considered: a "hydrophobic" defect that blocks the drop in front and a "hydrophilic" one that holds it at the back. Two different types of depinning leading to sliding motion are identified, and the resulting stick-slip motion is studied numerically. 相似文献
976.
Lenka V. Tamayo Juan F. Torres Johisner Llanos‐Penagos Jorge A. Caldern Edgar Nagles Olimpo García‐Beltrn John J. Hurtado 《Electroanalysis》2019,31(12):2429-2436
A new microcomposite with copper(II) complex and carbon paste (CuC/CPE) was developed to determine the uric acid (UA) content in the presence of dopamine (DP) and was characterized via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and energy dispersive spectroscopy (EDS). The results showed high selectivity for UA compared with DP because the anodic peak currents for DP were near those of a CPE without Cuc and were considerably increased for UA. The UA and DP increases were 86.9 % and 14.3 %, respectively, according to CV and 96.6 % and 25.5 %, respectively, according to square wave voltammetry (SWV) with the CuC/CPE. Moreover, the anodic peak separation for UA and DP was 0.17 V. With optimal parameters (pH, 3.3; adsorption time(tADS), 30 s;adsorption potential (EADS), 0.10 V), the anodic peak currents for UA were proportional to concentrations between 1.6 and 14.4 μmol L?1 using standard solutions with UA concentrations ranging from 8.0–40.5 μmol L?1 and real samples. The UA detection limit was 0.13 μmol L?1. The new sensor was used to determine the UA contentin human urine samples, and the method was checked with a urine chemistry control from Bio‐Rad based on human urine spiked with quantities of UA and showed a recovery between 84 % and 106 % at concentrations below 10.0 μmol L?1. 相似文献
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